seekable_stream_encoder.c

这是著名的TCPMP播放器在WINDWOWS,和WINCE下编译通过的源程序.笔者对其中的LIBMAD库做了针对ARM MPU的优化. 并增加了词幕功能.

FLAC_API FLAC__bool FLAC__seekable_stream_encoder_get_do_escape_coding(const FLAC__SeekableStreamEncoder *encoder)
{
	FLAC__ASSERT(0 != encoder);
	FLAC__ASSERT(0 != encoder->private_);
	return FLAC__stream_encoder_get_do_escape_coding(encoder->private_->stream_encoder);
}

FLAC_API FLAC__bool FLAC__seekable_stream_encoder_get_do_exhaustive_model_search(const FLAC__SeekableStreamEncoder *encoder)
{
	FLAC__ASSERT(0 != encoder);
	FLAC__ASSERT(0 != encoder->private_);
	return FLAC__stream_encoder_get_do_exhaustive_model_search(encoder->private_->stream_encoder);
}

FLAC_API unsigned FLAC__seekable_stream_encoder_get_min_residual_partition_order(const FLAC__SeekableStreamEncoder *encoder)
{
	FLAC__ASSERT(0 != encoder);
	FLAC__ASSERT(0 != encoder->private_);
	return FLAC__stream_encoder_get_min_residual_partition_order(encoder->private_->stream_encoder);
}

FLAC_API unsigned FLAC__seekable_stream_encoder_get_max_residual_partition_order(const FLAC__SeekableStreamEncoder *encoder)
{
	FLAC__ASSERT(0 != encoder);
	FLAC__ASSERT(0 != encoder->private_);
	return FLAC__stream_encoder_get_max_residual_partition_order(encoder->private_->stream_encoder);
}

FLAC_API unsigned FLAC__seekable_stream_encoder_get_rice_parameter_search_dist(const FLAC__SeekableStreamEncoder *encoder)
{
	FLAC__ASSERT(0 != encoder);
	FLAC__ASSERT(0 != encoder->private_);
	return FLAC__stream_encoder_get_rice_parameter_search_dist(encoder->private_->stream_encoder);
}

FLAC_API FLAC__uint64 FLAC__seekable_stream_encoder_get_total_samples_estimate(const FLAC__SeekableStreamEncoder *encoder)
{
	FLAC__ASSERT(0 != encoder);
	FLAC__ASSERT(0 != encoder->private_);
	return FLAC__stream_encoder_get_total_samples_estimate(encoder->private_->stream_encoder);
}

FLAC_API FLAC__bool FLAC__seekable_stream_encoder_process(FLAC__SeekableStreamEncoder *encoder, const FLAC__int32 * const buffer[], unsigned samples)
{
	FLAC__ASSERT(0 != encoder);
	FLAC__ASSERT(0 != encoder->private_);
	if(!FLAC__stream_encoder_process(encoder->private_->stream_encoder, buffer, samples)) {
		encoder->protected_->state = FLAC__SEEKABLE_STREAM_ENCODER_STREAM_ENCODER_ERROR;
		return false;
	}
	else
		return true;
}

/* 'samples' is channel-wide samples, e.g. for 1 second at 44100Hz, 'samples' = 44100 regardless of the number of channels */
FLAC_API FLAC__bool FLAC__seekable_stream_encoder_process_interleaved(FLAC__SeekableStreamEncoder *encoder, const FLAC__int32 buffer[], unsigned samples)
{
	FLAC__ASSERT(0 != encoder);
	FLAC__ASSERT(0 != encoder->private_);
	if(!FLAC__stream_encoder_process_interleaved(encoder->private_->stream_encoder, buffer, samples)) {
		encoder->protected_->state = FLAC__SEEKABLE_STREAM_ENCODER_STREAM_ENCODER_ERROR;
		return false;
	}
	else
		return true;
}

/***********************************************************************
 *
 * Private class methods
 *
 ***********************************************************************/

void set_defaults_(FLAC__SeekableStreamEncoder *encoder)
{
	FLAC__ASSERT(0 != encoder);
	FLAC__ASSERT(0 != encoder->private_);
	FLAC__ASSERT(0 != encoder->protected_);

	encoder->private_->seek_callback = 0;
	encoder->private_->tell_callback = 0;
	encoder->private_->write_callback = 0;
	encoder->private_->client_data = 0;

	encoder->private_->seek_table = 0;
}

FLAC__StreamEncoderWriteStatus write_callback_(const FLAC__StreamEncoder *unused, const FLAC__byte buffer[], unsigned bytes, unsigned samples, unsigned current_frame, void *client_data)
{
	FLAC__SeekableStreamEncoder *encoder = (FLAC__SeekableStreamEncoder*)client_data;
	FLAC__StreamEncoderWriteStatus status;
	FLAC__uint64 output_position;

	(void)unused; /* silence compiler warning about unused parameter */
	FLAC__ASSERT(encoder->private_->stream_encoder == unused);

	if(encoder->private_->tell_callback(encoder, &output_position, encoder->private_->client_data) != FLAC__SEEKABLE_STREAM_ENCODER_TELL_STATUS_OK)
		return encoder->protected_->state = FLAC__SEEKABLE_STREAM_ENCODER_TELL_ERROR;

	/*
	 * Watch for the STREAMINFO block and first SEEKTABLE block to go by and store their offsets.
	 */
	if(samples == 0) {
		FLAC__MetadataType type = (buffer[0] & 0x7f);
		if(type == FLAC__METADATA_TYPE_STREAMINFO)
			encoder->protected_->streaminfo_offset = output_position;
		else if(type == FLAC__METADATA_TYPE_SEEKTABLE && encoder->protected_->seektable_offset == 0)
			encoder->protected_->seektable_offset = output_position;
	}

	/*
	 * Mark the current seek point if hit (if audio_offset == 0 that
	 * means we're still writing metadata and haven't hit the first
	 * frame yet)
	 */
	if(0 != encoder->private_->seek_table && encoder->protected_->audio_offset > 0 && encoder->private_->seek_table->num_points > 0) {
		const unsigned blocksize = FLAC__stream_encoder_get_blocksize(encoder->private_->stream_encoder);
		const FLAC__uint64 frame_first_sample = encoder->private_->samples_written;
		const FLAC__uint64 frame_last_sample = frame_first_sample + (FLAC__uint64)blocksize - 1;
		FLAC__uint64 test_sample;
		unsigned i;
		for(i = encoder->private_->first_seekpoint_to_check; i < encoder->private_->seek_table->num_points; i++) {
			test_sample = encoder->private_->seek_table->points[i].sample_number;
			if(test_sample > frame_last_sample) {
				break;
			}
			else if(test_sample >= frame_first_sample) {
				encoder->private_->seek_table->points[i].sample_number = frame_first_sample;
				encoder->private_->seek_table->points[i].stream_offset = output_position - encoder->protected_->audio_offset;
				encoder->private_->seek_table->points[i].frame_samples = blocksize;
				encoder->private_->first_seekpoint_to_check++;
				/* DO NOT: "break;" and here's why:
				 * The seektable template may contain more than one target
				 * sample for any given frame; we will keep looping, generating
				 * duplicate seekpoints for them, and we'll clean it up later,
				 * just before writing the seektable back to the metadata.
				 */
			}
			else {
				encoder->private_->first_seekpoint_to_check++;
			}
		}
	}

	status = encoder->private_->write_callback(encoder, buffer, bytes, samples, current_frame, encoder->private_->client_data);

	if(status == FLAC__STREAM_ENCODER_WRITE_STATUS_OK) {
		encoder->private_->samples_written += samples;
	}
	else
		encoder->protected_->state = FLAC__SEEKABLE_STREAM_ENCODER_WRITE_ERROR;

	return status;
}

void metadata_callback_(const FLAC__StreamEncoder *unused, const FLAC__StreamMetadata *metadata, void *client_data)
{
	FLAC__SeekableStreamEncoder *encoder = (FLAC__SeekableStreamEncoder*)client_data;
	FLAC__byte b[max(6, FLAC__STREAM_METADATA_SEEKPOINT_LENGTH)];
	const FLAC__uint64 samples = metadata->data.stream_info.total_samples;
	const unsigned min_framesize = metadata->data.stream_info.min_framesize;
	const unsigned max_framesize = metadata->data.stream_info.max_framesize;
	const unsigned bps = metadata->data.stream_info.bits_per_sample;

	FLAC__ASSERT(metadata->type == FLAC__METADATA_TYPE_STREAMINFO);

	/* We get called by the stream encoder when the encoding process
	 * has finished so that we can update the STREAMINFO and SEEKTABLE
	 * blocks.
	 */

	(void)unused; /* silence compiler warning about unused parameter */
	FLAC__ASSERT(encoder->private_->stream_encoder == unused);

	/*@@@ reopen callback here?  The docs currently require user to open files in update mode from the start */

	/* All this is based on intimate knowledge of the stream header
	 * layout, but a change to the header format that would break this
	 * would also break all streams encoded in the previous format.
	 */

	/*
	 * Write MD5 signature
	 */
	{
		const unsigned md5_offset =
		FLAC__STREAM_METADATA_HEADER_LENGTH +
		(
			FLAC__STREAM_METADATA_STREAMINFO_MIN_BLOCK_SIZE_LEN +
			FLAC__STREAM_METADATA_STREAMINFO_MAX_BLOCK_SIZE_LEN +
			FLAC__STREAM_METADATA_STREAMINFO_MIN_FRAME_SIZE_LEN +
			FLAC__STREAM_METADATA_STREAMINFO_MAX_FRAME_SIZE_LEN +
			FLAC__STREAM_METADATA_STREAMINFO_SAMPLE_RATE_LEN +
			FLAC__STREAM_METADATA_STREAMINFO_CHANNELS_LEN +
			FLAC__STREAM_METADATA_STREAMINFO_BITS_PER_SAMPLE_LEN +
			FLAC__STREAM_METADATA_STREAMINFO_TOTAL_SAMPLES_LEN
		) / 8;

		if(encoder->private_->seek_callback(encoder, encoder->protected_->streaminfo_offset + md5_offset, encoder->private_->client_data) != FLAC__SEEKABLE_STREAM_ENCODER_SEEK_STATUS_OK) {
			encoder->protected_->state = FLAC__SEEKABLE_STREAM_ENCODER_SEEK_ERROR;
			return;
		}
		if(encoder->private_->write_callback(encoder, metadata->data.stream_info.md5sum, 16, 0, 0, encoder->private_->client_data) != FLAC__STREAM_ENCODER_WRITE_STATUS_OK) {
			encoder->protected_->state = FLAC__SEEKABLE_STREAM_ENCODER_WRITE_ERROR;
			return;
		}
	}

	/*
	 * Write total samples
	 */
	{
		const unsigned total_samples_byte_offset =
		FLAC__STREAM_METADATA_HEADER_LENGTH +
		(
			FLAC__STREAM_METADATA_STREAMINFO_MIN_BLOCK_SIZE_LEN +
			FLAC__STREAM_METADATA_STREAMINFO_MAX_BLOCK_SIZE_LEN +
			FLAC__STREAM_METADATA_STREAMINFO_MIN_FRAME_SIZE_LEN +
			FLAC__STREAM_METADATA_STREAMINFO_MAX_FRAME_SIZE_LEN +
			FLAC__STREAM_METADATA_STREAMINFO_SAMPLE_RATE_LEN +
			FLAC__STREAM_METADATA_STREAMINFO_CHANNELS_LEN +
			FLAC__STREAM_METADATA_STREAMINFO_BITS_PER_SAMPLE_LEN
			- 4
		) / 8;

		b[0] = ((FLAC__byte)(bps-1) << 4) | (FLAC__byte)((samples >> 32) & 0x0F);
		b[1] = (FLAC__byte)((samples >> 24) & 0xFF);
		b[2] = (FLAC__byte)((samples >> 16) & 0xFF);
		b[3] = (FLAC__byte)((samples >> 8) & 0xFF);
		b[4] = (FLAC__byte)(samples & 0xFF);
		if(encoder->private_->seek_callback(encoder, encoder->protected_->streaminfo_offset + total_samples_byte_offset, encoder->private_->client_data) != FLAC__SEEKABLE_STREAM_ENCODER_SEEK_STATUS_OK) {
			encoder->protected_->state = FLAC__SEEKABLE_STREAM_ENCODER_SEEK_ERROR;
			return;
		}
		if(encoder->private_->write_callback(encoder, b, 5, 0, 0, encoder->private_->client_data) != FLAC__STREAM_ENCODER_WRITE_STATUS_OK) {
			encoder->protected_->state = FLAC__SEEKABLE_STREAM_ENCODER_WRITE_ERROR;
			return;
		}
	}

	/*
	 * Write min/max framesize
	 */
	{
		const unsigned min_framesize_offset =
		FLAC__STREAM_METADATA_HEADER_LENGTH +
		(
			FLAC__STREAM_METADATA_STREAMINFO_MIN_BLOCK_SIZE_LEN +
			FLAC__STREAM_METADATA_STREAMINFO_MAX_BLOCK_SIZE_LEN
		) / 8;

		b[0] = (FLAC__byte)((min_framesize >> 16) & 0xFF);
		b[1] = (FLAC__byte)((min_framesize >> 8) & 0xFF);
		b[2] = (FLAC__byte)(min_framesize & 0xFF);
		b[3] = (FLAC__byte)((max_framesize >> 16) & 0xFF);
		b[4] = (FLAC__byte)((max_framesize >> 8) & 0xFF);
		b[5] = (FLAC__byte)(max_framesize & 0xFF);
		if(encoder->private_->seek_callback(encoder, encoder->protected_->streaminfo_offset + min_framesize_offset, encoder->private_->client_data) != FLAC__SEEKABLE_STREAM_ENCODER_SEEK_STATUS_OK) {
			encoder->protected_->state = FLAC__SEEKABLE_STREAM_ENCODER_SEEK_ERROR;
			return;
		}
		if(encoder->private_->write_callback(encoder, b, 6, 0, 0, encoder->private_->client_data) != FLAC__STREAM_ENCODER_WRITE_STATUS_OK) {
			encoder->protected_->state = FLAC__SEEKABLE_STREAM_ENCODER_WRITE_ERROR;
			return;
		}
	}

	/*
	 * Write seektable
	 */
	if(0 != encoder->private_->seek_table && encoder->private_->seek_table->num_points > 0 && encoder->protected_->seektable_offset > 0) {
		unsigned i;

		FLAC__format_seektable_sort(encoder->private_->seek_table);

		FLAC__ASSERT(FLAC__format_seektable_is_legal(encoder->private_->seek_table));

		if(encoder->private_->seek_callback(encoder, encoder->protected_->seektable_offset + FLAC__STREAM_METADATA_HEADER_LENGTH, encoder->private_->client_data) != FLAC__SEEKABLE_STREAM_ENCODER_SEEK_STATUS_OK) {
			encoder->protected_->state = FLAC__SEEKABLE_STREAM_ENCODER_SEEK_ERROR;
			return;
		}

		for(i = 0; i < encoder->private_->seek_table->num_points; i++) {
			FLAC__uint64 xx;
			unsigned x;
			xx = encoder->private_->seek_table->points[i].sample_number;
			b[7] = (FLAC__byte)xx; xx >>= 8;
			b[6] = (FLAC__byte)xx; xx >>= 8;
			b[5] = (FLAC__byte)xx; xx >>= 8;
			b[4] = (FLAC__byte)xx; xx >>= 8;
			b[3] = (FLAC__byte)xx; xx >>= 8;
			b[2] = (FLAC__byte)xx; xx >>= 8;
			b[1] = (FLAC__byte)xx; xx >>= 8;
			b[0] = (FLAC__byte)xx; xx >>= 8;
			xx = encoder->private_->seek_table->points[i].stream_offset;
			b[15] = (FLAC__byte)xx; xx >>= 8;
			b[14] = (FLAC__byte)xx; xx >>= 8;
			b[13] = (FLAC__byte)xx; xx >>= 8;
			b[12] = (FLAC__byte)xx; xx >>= 8;
			b[11] = (FLAC__byte)xx; xx >>= 8;
			b[10] = (FLAC__byte)xx; xx >>= 8;
			b[9] = (FLAC__byte)xx; xx >>= 8;
			b[8] = (FLAC__byte)xx; xx >>= 8;
			x = encoder->private_->seek_table->points[i].frame_samples;
			b[17] = (FLAC__byte)x; x >>= 8;
			b[16] = (FLAC__byte)x; x >>= 8;
			if(encoder->private_->write_callback(encoder, b, 18, 0, 0, encoder->private_->client_data) != FLAC__STREAM_ENCODER_WRITE_STATUS_OK) {
				encoder->protected_->state = FLAC__SEEKABLE_STREAM_ENCODER_WRITE_ERROR;
				return;
			}
		}
	}
}